The invention relates to the partial or complete utilization of a pressurized-gas cylinder known per se for compressed, liquefied or dissolved gases.
Gases and gas mixtures are generally stored and transported in pressurized-gas containers. According to the German ordinance on pressure vessels, these are containers in which an overpressure greater than 1 bar can be produced at 15xc2x0 C. Information on the status of safety technology with respect to material, production, calculation, equipment, labeling, testing and operation of the pressurized-gas containers, and on construction, testing and operation of the filling plants, is given by the German codes of practice for pressurized gases (TRG). The TRG differentiate between gases and gas mixtures according to their chemical and physical behavior and establish the pressurized-gas containers to be used, including their equipment components, their test intervals, the filling factors and filling pressures.
The most usual pressurized-gas containers are pressurized-gas cylinders of steel and aluminum for compressed, liquefied or dissolved gases having a maximum filling pressure up to 200 bar. Increasingly, the users are demanding pressurized-gas containers having a maximum filling pressure up to 300 bar. These 300 bar pressurized-gas containers are likewise fabricated from steel or aluminum. For special applications, corrosion-resistant stainless steel (DE 37 36 579 A1) is also used.
To decrease the weight of such 300 bar pressurized-gas cylinders, composite gas cylinders (composite cylinders) are recently being used by the gas producers. Composite gas cylinders consist of a seamless metal liner which is wrapped over an important part of its length with composite fibers of glass, carbon, aramid or wire. Aramid is taken to mean organic fibers of poly(phenylene terephthalamide), which include Kevlar and Twaron. Aramid and carbon fibers are lighter than glass fibers, with identical or better strength properties and good impact strength.
Composite gas cylinders of this type are expensive to produce. In addition, there is the fact that, with the charging of all of the gas types which are currently technically possible into 300 bar pressurized-gas cylinders, there is a high potential for disposal of used 200 bar pressurized-gas cylinders.
The object underlying the invention is to provide a composite gas cylinder which can be produced considerably more cheaply.
In accordance with this invention a composite cylinder comprises a liner wrapped over a substantial part of its length with composite fibers, and the liner is a pressurized-gas cylinder for compressed, liquefied or dissolved gases, which is currently in circulation.